Twitter CEO Jack Dorsey has been very open about his unusual eating habits. In the past, Dorsey has experimented with everything from the more mainstream vegan and Paleo fads to a more rigid routine of intermittent fasting.

Now, Dorsey’s unusual eating habits have again garnered a lot of attention, and criticism, after he discussed them on a recent podcast episode.

He told host Ben Greenfield – a fitness influencer who tweeted “anti-vaxx” comments last month – that he eats only one meal a day during the workweek, then fasts for the whole weekend.

“The first time I did it, like day three, I felt like I was hallucinating,” Dorsey said. “It was a weird state to be in. But as I did it the next two times, it just became so apparent to me how much of our days are centered around meals and how – the experience I had was when I was fasting for much longer, how time really slowed down.”

It sounds like Jack Dorsey might have a serious eating disorder. Walking 5 miles a day while only consuming one meal per weekday and no meals ion weekends is not a wellness hack…it’s a disease. https://t.co/KGQtDGgSnR

Steve Jobs was known to go weeks eating only one or two foods at a time – once, it was strictly carrots and apples. Mark Zuckerberg made it his “personal challenge” in 2011 to eat only meat from animals he’d killed himself.

Many are pulled to the diet because when you can eat – in the defined window of the day – you don’t have to count calories or ban carbs. Dorsey said his one meal a day includes fish, chicken, or steak with a side of vegetables.